"Assuming the necessary classes have been imported, which of the following statements will compile without error?"

Question

"Assuming the necessary classes have been imported, which of the following statements will compile without error?"

Object obj = new Calendar();
Calendar c = new Calendar();
GregorianCalender d = new Object();
Object e = new GregorianCalender();

I think it may be the second one, but I'd like someone to double check me. Thank you :)

Answer 1

Answers for the quiz

1. B- A class needs to be a parent of several sub classes, but the class itself represents too broad of a concept to make meaningful objects
2. C- public abstract String getAbbreviatnio();
3. D- Alpha[] c = new Alpha[100];
4. B- public abstract int add(int a, int b);
5. B- it is italicized
6. D- public abstract class Delta{
public void print(){
System,out.println():
}
}
7. D- Echo h = new Foxtrot();
8. B- The subclass must override the method
9. B- Character
10. D- Object e = new GergorianCalender(); <-- Your question

Answer 2

Sorry, I meant I think it may be the first answer.

Answer 3

To determine which of the statements will compile without error, let's go through each statement one by one:

1. Object obj = new Calendar();
Here, we are trying to create a new instance of the `Calendar` class and assign it to the variable `obj`, which is of type `Object`. This statement will compile without error because `Calendar` is a subclass of `Object`. In Java, it is always possible to assign an instance of a subclass to a variable of its superclass.

2. Calendar c = new Calendar();
This statement tries to create a new instance of the `Calendar` class and assign it to the variable `c`, which is of type `Calendar`. This statement will also compile without error because we are directly creating an instance of the `Calendar` class, which is allowed.

3. GregorianCalendar d = new Object();
In this statement, we are trying to create a new instance of the `Object` class and assign it to the variable `d`, which is of type `GregorianCalendar`. However, this will result in a compilation error. The `Object` class is a superclass of `GregorianCalendar`, so it is not possible to assign an instance of a superclass to a variable of its subclass.

4. Object e = new GregorianCalendar();
This statement attempts to create a new instance of the `GregorianCalendar` class and assign it to the variable `e`, which is of type `Object`. This statement will compile without error because `GregorianCalendar` is a subclass of `Object`. As mentioned before, in Java, it is always possible to assign an instance of a subclass to a variable of its superclass.

So, in conclusion, the statements that will compile without error are:

1. Object obj = new Calendar();
2. Calendar c = new Calendar();
4. Object e = new GregorianCalendar();

Therefore, the correct statement in this case would be the second one: `Calendar c = new Calendar();`.